1. Field of the Invention
This invention relates to a functional alcohol releasing substance which gradually releases a functional alcohol and to a composition such as of a detergent or softening agent, which contains the functional alcohol releasing substance.
2. Description of the Related Art
In a fragrance, a desired aroma is created by blending a large number of aromatic components so-called top note, middle note and base note having different volatility. During the use of the fragrance, components having higher volatility vaporize in priority and, as a result, the aroma of the fragrance changes with the lapse of time, thus posing a problem in that the aroma cannot be maintained constantly for a prolonged period of time. A gel-like aromatic composition in which a fragrance is included in microcapsules and dispersed in a gel base material is known as a means for solving such a problem (JP-A-63-260567; the termxe2x80x9cJP-Axe2x80x9d as used herein means an xe2x80x9cunexamined published Japanese patent applicationxe2x80x9d). Though this method is effective in gel-like preparations, the desired effect cannot be obtained in the case of liquid preparations having low viscosity due to generation of floating and precipitation of microcapsules.
In addition to the above, a precursor of fragrance raw material in which a sugar and an amino acid are added to a fragrance raw material and a technique for gradually releasing the fragrance raw material by allowing an enzyme to act upon the precursor have been disclosed (JP-A-4-170961). This method, however, has problems in that its effect in the actual use system varies depending on the presence or absence of the hydrolyzing enzyme and, when the precursor and hydrolyzing enzyme are simultaneously blended in a product system, hydrolysis progresses in the product. It also poses the same problems in volatile antibacterial and antifungal agents, so that it is difficult to maintain their effects. In addition, even a nonvolatile substance, e.g. in the case of a water-soluble substance, cannot maintain its effect due to its washing with water.
On the other hand, WO 96/38528 discloses a betaine ester quaternary ammonium salt derivative which can gradually release a fragrance raw material alcohol. However, this betaine ester quaternary ammonium salt is apt to cause side reactions at the time of synthesis and has a considerably high hydrolyzing rate even in a neutral to weakly acidic aqueous solution, so that it has a disadvantage of poor blending stability.
An object of the invention is to provide a functional substance releasing compound which can be stably blended independent of the form and use of preparations and can gradually release a functional substance constantly for a prolonged period of time in an actual use system.
The invention is a substance which is a betaine ester of a functional alcohol, in which it has an amido bond in its molecule and releases the functional alcohol, and a composition containing the same.
The term betaine ester as used herein means a structure in which a free acid as the hydration product of betaine and an alcohol are esterificated.
As the functional alcohol releasing substance of the invention, a compound represented by a general formula (I) (to be referred to as betaine ester (I) hereinafter) can be exemplified: 
wherein each of R1, R2 and R3 independently represents hydrogen atom or a straight- or branched-chain alkyl or alkenyl group having from 1 to 30 carbon atoms, Y represents a straight- or branched-chain alkylene group having from 1 to 4 carbon atoms, Z is a group represented by xe2x80x94R5(OA) nxe2x80x94 (wherein R5 is a straight- or branched-chain alkylene group having from 1 to 30 carbon atoms, and A is a straight- or branched-chain alkylene group having from 2 to 4 carbon atoms, and n is a number of from 0 to 10), R4 represents a residue in which one OH is removed from a functional alcohol having at least one hydroxyl group in its molecule, illustratively, R4 represents a saturated or unsaturated aliphatic hydrocarbon group or aromatic hydrocarbon group having from 1 to 11 carbon atoms, or an alkadienyl group, alkatrienyl group, aryl group, arylalkyl group or monocyclic, bicyclic or tricyclic terpene hydrocarbon group, each having from 12 to 30 carbon atoms, wherein a part of the hydrogen atoms on the hydrocarbon group of R4 may be substituted by a halogen atom or hydroxyl group, the methylene group in the hydrocarbon group of R4 may be substituted by carbonyl group, amido bond, oxygen atom or sulfur atom, the methyl group may be substituted by formyl group or xe2x80x94CONH2, the carbon-carbon double bond may be substituted by epoxy group and, when isomers are present in R4, it may be a mixture of isomers, and Xxe2x88x92 represents an anion.
In this case, the alkyl group, alkenyl group and alkylene group may have a substituent group, and examples of the substituent group include an aryl group such as phenyl group, an alkoxy group such as methoxy group or ethoxy group and an aryloxy group such as phenoxy group.
The betaine ester (I) can be obtained for example by allowing a compound represented by a general formula (III) (to be referred to as compound (III) hereinafter) to react with a compound represented by a general formula (IV) (to be referred to as compound (IV) hereinafter) in the presence of a solvent: 
wherein R1, R2, R3, R4, X, Y and Z are as defined in the foregoing.
Examples of the solvent to be used include diethyl ether, acetone and chloroform which are selected in response to the solubility of each material. The reaction temperature can be selected within the range of from 15 to 100xc2x0 C. depending on the boiling point of the solvent used and is preferably from 25 to 50xc2x0 C., more preferably from 40 to 45xc2x0 C. Regarding the blending ratio of the compound (III) and compound (IV), it is desirable to use excess amount of the compound (IV) in order to increase the reaction ratio and facilitate purification of the product, and it is preferably within the range of from 1:1 to 1:1.2 by molar ratio for practical purpose.
The compound (III), when the number of carbons of the acyl group represented by R3COxe2x80x94 is 8 or more, can be quantitatively obtained by heat-melting the corresponding fatty acid at 160 to 180xc2x0 C. in an atmosphere of nitrogen and slowly adding a compound represented by a general formula (V) dropwise thereto, thereby effecting dehydration condensation. Also, when the number of carbons of the acyl group represented by R3COxe2x80x94 is less than 8, it can be obtained by allowing an acid anhydride or acid chloride of the corresponding fatty acid to react with the compound of general formula (V). 
In this formula, R1, R2 and Z are as defined in the foregoing.
The compound (IV) can be obtained by condensing a compound represented by a general formula (VI) with an alcohol represented by a general formula (VII) in the presence of amine as a base. 
In the above formulae, R4, X and Y are as defined in the foregoing, and B represents a halogen atom.
Among compounds of the betaine ester (I), particularly preferred is a compound represented by a general formula (II) (to be referred to as betaine ester (II) hereinafter). 
In this formula, R1, R2, R3, R4, n and Xxe2x88x92 are as defined in the foregoing, R6represents hydrogen atom or methyl group, a is 1 or 2.
In the betaine ester (II), each of R1 and R2 is preferably a group having from 1 to 4 carbon atoms, more preferably methyl group. R3 is preferably a group having from 1 to 22 carbon atoms. Preferably, n is from 0 to 3. Examples of the anion represented by Xxe2x88x92 include halogen ions, sulfate ion, hydrogensulfate ion and perchlorate ion, of which chlorine ion is preferred.
Also, the following can be cited as illustrative examples of the group represented by R4.
(1) Saturated or unsaturated, substituted or unsubstituted aliphatic hydrocarbon group having from 1 to 11 carbon atoms:
A reside in which one hydroxyl group is removed from an aliphatic alcohol such as ethanol, leaf alcohol (cis-3-hexenol), 3-octenol, 2,4-dimethyl-3-cyclohexene-1-methanol, 4-isopropylcyclohexanol, 4-isopropylcyclohexylmethanol, 1-(4-isopropylcyclohexyl)ethanol, p-t-butylcyclohexanol, o-t-butylcyclohexanol, 9-decenol, linalool, geraniol, nerol, citronellol, rhodinol, dimethyloctanol, hydroxycitronellol, tetrahydrolinalool, lavandulol, mugol, myrcenol, terpineol, L-menthol, borneol, isopulegol, tetrahydromugol, nopol or glycerol.
(2) Substituted or unsubstituted aromatic hydrocarbon group having from 1 to 11 carbon atoms:
A reside in which one hydroxyl group is removed from an aromatic alcohol such as benzyl alcohol, xcex2-phenylethyl alcohol, xcex3-phenylpropyl alcohol, cinnamic alcohol, anisic alcohol, dimethylbenzylcarbinol, methylphenylcarbinol, dimethylphenylcarbinol, phenoxyethyl alcohol, styrallyl alcohol, dimethylphenylethylcarbinol, thymol, carvacrol, eugenol, isoeugenol, ethyl vanillin, metha-chloroxylenol, 2,4-dichlorophenol, 2,4-dichlorobenzyl alcohol, hinokithiol or 3-methyl-4-isopropylphenol.
(3) Alkadienyl group or alkatrienyl group having from 12 to 30 carbon atoms:
A reside in which one hydroxyl group is removed from a compound such as farnesol or nerolidol.
(4) Aryl group or arylalkyl group having from 12 to 30 carbon atoms:
A reside in which one hydroxyl group is removed from a compound such as 2,2-dimethyl-3-(3-methylphenyl)propanol, 3-methyl-5-phenylpentanol, phenylethylmethylethylcarbinol, trichlosan, capsaicin or tocopherol.
(5) Monocyclic, bicyclic or tricyclic terpene hydrocarbon group having from 12 to 30 carbon atoms:
A reside in which one hydroxyl group is removed from a compound such as ambrinol, 1-(2-t-butylcyclohexyloxy)-2-butanol, pentamethylcyclohexylpropanol, 1-(2,2,6-trimethylcyclohexyl)-3-hexanol, santalol, cedrol, vetiverol or patchouli alcohol.
Since the functional alcohol releasing substance of the invention can release functional alcohols such as perfumes and antibacterial and antifungal agents gradually for a prolonged period of time, it can be used alone or in combination with other components as ingredients of, e.g., soaps, shampoos, detergents, cosmetics, spray products, deodorants, aromatics, bathing goods, coloring agents, hair colors, antibacterial agents, antifungal agents, vapor proofing agents, bedclothes, towels, clothes, tissues, sands for pet toilet use, chewing gums, cosmetics for pack use, clay compositions for handicraft use, absorbable articles, cosmetics for massage use, paints, agricultural chemicals, medicaments and inks.
The composition of the invention contains the functional alcohol releasing substance, and the amount of the functional alcohol releasing substance to be contained in the composition of the invention is preferably from 0.01 to 90% by weight, more preferably from 0.5 to 50% by weight, based on the composition, though it varies depending, e.g., on the kind of composition and the kind of functional alcohol of interest.
The composition of the invention is particularly useful as, e.g., a softening agent composition containing a textile conditioner or softening agent component, a detergent composition for clothing use containing a detergent component or a detergent composition for hard surface use.
Examples of the textile conditioner or softening agent component include quaternary ammonium salts, amines and neutral salts of amines, particularly an acid salt of a quaternary ammonium compound or tertiary amine compound having in its molecule one or more ester groups and/or amido groups and two or more alkyl groups or alkenyl groups having from 11 to 20 carbon atoms, an acid salt of a quaternary ammonium compound or tertiary amine compound having in its molecule one alkyl group or alkenyl group having from 11 to 20 carbon atoms and an amphoteric surface active agent having in its molecule one alkyl group or alkenyl group having from 6 to 20 carbon atoms. Also, for the purpose of further improving the softening performance, an alkylene oxide addition product of a higher alcohol or amine, a higher fatty acid or a salt thereof may be added as occasion demands. The amount of the textile conditioner or softening agent component to be used in the composition of the invention is preferably from 1 to 50% by weight, more preferably from 5 to 20% by weight.
Examples of the detergent component to be used in the composition of the invention include anionic surface active agents such as a polyoxyalkylene alkyl ether sulfate, an alkyl sulfate, an alkylbenzene sulfonate, an xcex1-olefin sulfonate, an alkane sulfonate, a fatty acid salt, an xcex1-sulfofatty acid ester salt, a polyoxyalkylene alkyl ether carboxylate and a polyoxyalkylene alkyl ether phosphate, nonionic surface active agents such as a polyoxyalkylene alkyl ether, an alkyl glucoside, mono- and dialkanolamides of a fatty acid and an active agent of Pluronic system, cationic surface active agents such as a quaternary ammonium salt and amphoteric surface active agents such as carbobetaine and sulfobetaine. Amount of the detergent component in the composition of the invention is preferably from 1 to 80% by weight, more preferably from 20 to 40% by weight, as a detergent composition for clothing use. As a detergent composition for hard surface use, it is preferably from 0.5 to 60% by weight, more preferably from 1 to 50% by weight, based on the composition.
As occasion demands, other additive agents used in general softening agents and detergents can be optionally added to the composition of the invention within such a range that they do not spoil effects of the invention.
Examples of the other additive agents which can be added include storage stabilizing agents such as lower alcohols including ethanol and isopropanol, a glycol, a polyol and alkylene oxide addition products thereof; chelating agents such as ethylenediamine tetraacetate, diethylenetriamine pentaacetate, sodium acid pyrophosphate, tetrasodium pyrophosphate, sodium tripolyphosphate, zeolite, ethylhydroxy diphosphonate, citric acid, dipicolinic acid, picolinic acid and 8-hydroxyquinoline; solubilizing agents such as sodium salts and potassium salts of toluenesulfonic acid and xylenesulfonic acid and urea; alkali agents such as sodium carbonate and an amorphous alkali metal silicate; viscosity adjusting agents such as a clay mineral and a water-soluble polymer; moisture keeping agents such as glycerol and sorbitol; feel improving agents such as cationic cellulose; extenders such as sodium sulfate; and a pH adjusting agent, a hydrotropic agent, an antifoaming agent, an antioxidant, an enzyme, a perfume, an antibacterial agent, a pigment and an antiseptic/antifungal agent.